A US men’s 9 is EU 42.5 at Nike and EU 42 2/3 at Adidas. New Balance calls it 42.5 as well, then asks which width you want. A shop that stocks all three brands ends up with those numbers in one size menu, and a customer who shops by EU size can order the wrong pair.
This guide is for sneaker shops and resellers who list Nike, Adidas and New Balance side by side. It covers how each brand writes its sizes and style codes, and how to set up your product data so the size menu, the size chart and the box agree.
One foot, three size charts
Here is a US men’s 9 on each brand’s chart.
| US men’s 9 | Nike | Adidas | New Balance |
|---|---|---|---|
| US women’s | 10.5 | 10 | 10.5 |
| UK | 8 | 8.5 | 8.5 |
| EU | 42.5 | 42 2/3 | 42.5 |
| JP or cm | 27 | 270 | 27 |
The Nike column comes from Nike’s size chart. The Adidas and New Balance columns come from retailer copies of their charts, at Marathon Sports and SportsShoes. Adidas prints JP sizes in millimeters, so its 270 is the same 27 cm.
Four things in that table catch sellers out.
UK sizes sit at different gaps. Nike puts UK a full size below US. Adidas and New Balance put it half a size below. A Nike UK 8 and an Adidas UK 8 are different shoes, and a size filter built on UK puts them in the same row.
Adidas counts EU sizes in thirds. Its run goes 41 1/3, 42, 42 2/3, 43 1/3, 44. A number field stores 42 2/3 as 42.67, a size nobody recognizes. Round it to 42.5 or 43 and you list a size Adidas doesn’t make. Keep EU sizes as text.
Women’s sizes use different offsets. Add 1.5 to a Nike or New Balance men’s size to get the women’s size. For Adidas, add 1. One formula for all three brands gets Adidas wrong by half a size.
The copies disagree too. SportsShoes prints two New Balance tables on the same page. One puts a US men’s 8 at EU 41.5, the other at EU 41.
So don’t convert sizes with a formula, yours or a plugin’s. Copy each brand’s own chart, and when the chart and the box disagree, trust the box.
Three formats of style code
A style code names one colorway of one model. StockX shows it on every listing, and buyers who already know the shoe search for it. Each brand builds it differently.
Nike uses six characters, a hyphen and three digits. DD1391-100 is the Dunk Low Retro in White/White/Black. The part before the hyphen names the model, and the three digits after it name the colorway.
Adidas gives each colorway one six-character code with no separate color part. B75806 is the Samba OG in Cloud White/Core Black/Clear Granite. You can’t read the model or the color from the code, so store the model name next to it.
New Balance packs more in. M990GL6 is the grey 990v6 Made in USA. Read it as M for men’s, 990 for the model, GL for the colorway and 6 for the version. The width isn’t part of it.
Whatever the format, give the style code its own field, one per colorway. It isn’t a SKU. A SKU names one size of one colorway, so a size run needs one per size. Build it from the style code and the size, like DD1391-100-9, and the SKU on a pick list tells you which box to pull.
New Balance adds a width
Most Nike and Adidas sneakers come in one width. New Balance sells many models in several. D is the standard men’s width and B the standard women’s, with 2E and 4E as the wider fits. The 990v6 above sells in D and 2E.
Width multiplies your variants. A colorway in 14 sizes is 14 variants. Offer it in D, 2E and 4E and it’s up to 42, because not every size comes in every width.
Make width a second option next to size. Don’t fold it into the size label. A size value of “9 2E” hides that pair from a customer who filters for size 9. Then create only the size and width pairs New Balance actually makes.
One product per colorway
Treat each colorway as its own product, not as a color option on one Dunk Low. Each colorway already has its own style code, photos and release date, and often its own price. As a color option, all of that gets squeezed into one record, with every colorway’s photos hanging off one product page.
Link the colorways through the model name instead. A collection or a related products block can then list every Samba OG you stock.
A record that works for all three brands
Pick the size system your customers shop in, and use it for the size option. That’s US men’s for a US store, and EU or UK for most of Europe. Put the brand’s other systems in a size chart per brand, copied from that brand’s chart.
| Field | Where it goes | Nike | Adidas | New Balance |
|---|---|---|---|---|
| Model | Product | Dunk Low Retro | Samba OG | 990v6 |
| Style code | Product | DD1391-100 | B75806 | M990GL6 |
| Colorway | Product | White/White/Black | Cloud White/Core Black/Clear Granite | Grey |
| Size | Variant option | US 9 | US 9 | US 9 |
| Width | Variant option | One width | One width | D or 2E |
| UK, EU, JP | Size chart per brand | 8, 42.5, 27 | 8.5, 42 2/3, 270 | 8.5, 42.5, 27 |
| SKU | Variant | DD1391-100-9 | B75806-9 | M990GL6-9-D |
Release date and upper material belong on the product too, since every size shares them.
Where Sellufy fits
Sellufy is a product information management system, or PIM, with Shopify and WooCommerce built in. In a sneaker catalog it holds what every size of a colorway shares.
- One product per colorway, with model, style code, colorway and release date as custom attributes.
- Custom attributes map to Shopify metafields, so the style code can show on the product page.
- Photos come from the built-in DAM and attach to the colorway they show.
- AI enrichment writes missing descriptions and attribute values. Type the style code yourself from the box, though. An AI tool can’t see the box, and it will make up a code that looks right.
- The same record publishes to a Shopify store and a WooCommerce store. Our Shopify and WooCommerce guides cover how each connection works.
Free lets you build a catalog of 50 products but doesn’t connect a store. Growth, at $9 a month, connects two stores and holds 250 products. The pricing page lists the larger plans.
Frequently asked questions
Is a Nike EU 42.5 the same size as an Adidas EU 42.5?
Adidas doesn’t make an EU 42.5. Its run goes from 42 to 42 2/3. The Adidas size that matches a Nike 42.5 is 42 2/3, since both are a US men’s 9.
Can I convert sneaker sizes with one chart?
No. Nike, Adidas and New Balance each convert US sizes to UK, EU and women’s sizes their own way. Use each brand’s chart, and check it against the box.
Where do I find the style code?
On the box label, and on the tag inside the shoe, usually behind the tongue.
Is the style code the same as the SKU?
No. One style code covers every size of a colorway. A SKU names one size, so build it from the style code plus the size.